T-ALL及T细胞株相关TCR Vβ基因谱系和克隆性分析  

Clonality and gene repertoire analysis of T-cell receptor Vβ associated with T-ALL and T cell strains

作　　者：黄梅娟[1] 李扬秋[1] 陈少华[1] 周羽竝[2] 杨力建[1] 韩素芳[1] 

机构地区：[1]暨南大学医学院血液病研究所,广东广州510632 [2]暨南大学医学院生物化学教研室,广东广州510632

出　　处：《免疫学杂志》2004年第6期439-442,共4页Immunological Journal

基　　金：国家自然科学基金 (39870 358);中德生物技术合作项目 (CHN0 2 31 9);广东省自然科学基金 (980 70 5);广东省科技计划项目 (2 0 0 2C1 0 4 0 50 1 );广州市科委重点科技攻关计划项目 (98 z 0 39 0 1 )资助

摘　　要：目的　了解T细胞 急性淋巴细胞白血病 (T ALL)患者外周血中的T细胞及T细胞株的TCRVβ基因谱系及其克隆性增殖情况。方法　利用RT PCR方法扩增 6个不同的T细胞株和 6例初发未治T ALL病人外周血单个核细胞中 2 4个TCRVβ基因的互补决定区 3(CDR3) ,PCR产物进一步经荧光标记和基因扫描分析CDR3长度而确定T细胞的克隆性 ,部分T细胞株的单克隆PCR产物进一步进行序列分析。结果　与正常人外周血表达全部 2 4个Vβ亚家族不同 ,6例T ALL病人分别表达 5～ 12个Vβ亚家族。 6例病人均存在 1个或多个Vβ亚家族的寡克隆或双克隆增殖T细胞 ,另外 ,还有一些Vβ亚家族多克隆模式发生改变 ,呈现寡克隆性增殖的趋势。T细胞株多显示为表达一个Vβ亚家族的单克隆T细胞 ,不同T细胞株的CDR3长度和序列不尽相同。结论　T ALL患者外周血T细胞的TCRVβ谱系出现限制性改变 ,均可检测到克隆性增殖T细胞 ,尚需进一步鉴定其性质 (肿瘤性或抗原特异性增殖 ) 。Objective To investigate the TCR Vβ gene repertoire, and to clonal expansion of T cells and T cell strains from peripheral blood of patients with T-cell acute lymphoblastic leukemia (T-ALL). Methods The complementarity determining region 3 (CDR3) of TCR Vβ 24 subfamily genes in peripheral blood mononuclear cell from 6 cases with untreated T-ALL and 6 T cell strains were amplified using RT-PCR. The PCR products were further labelled by fluorescein and then analyzed by genescan technique for detecting the CDR3 length, and as a result, the clonality of T cells was determined. Some monoclonal PCR products from T cell strains were analyzed by sequencing to define the sequence of CDR3. Results Six T-ALL cases expressed 5-12 Vβ subfamilies while normal individuals expressed all 24 Vβ subfamilies in peripheral blood. Oligoclonal and biclonal expansion of T cells in one or more Vβ subfamilies were found in each of the 6 cases. In addition, polyclonal patterns in some Vβ subfamilies appeared the trend of oligoclonal expansion. Only one Vβ subfamily's monoclonal expanded T cell could be identified in most T cell strains. Sequences from different T cell strains displayed different CDR3 length and sequences. Conclusion Restrictive changes of TCR Vβ repertoire could be found in peripheral blood T cells from patients with T-ALL.The clonal expansions of T cells are detected in the 6 cases with T-ALL. However, their property (clonal expansion leukemic cells or leukemia antigen-specific expansion T cells) should be further characterized. The results indicate that the identification of TCR Vβ repertoire and clonality of T cells in T-ALL may play a certain role in the detection of minimal residual disease and the design of idiotypic anti-leukemia vaccine.

关 键 词：T细胞-急性淋巴细胞白血病 T细胞株 T细胞受体VΒ基因 T细胞克隆性 

分 类 号：R733.7[医药卫生—肿瘤]